2005 MITSUBISHI 380 relay

14-1
GROUP 14
ENGINE COOLING
CONTENTS
GENERAL DESCRIPTION. . . . . . . . .14-2
SPECIAL TOOL . . . . . . . . . . . . . . . . .14-2
ENGINE COOLING DIAGNOSIS . . . .14-2
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . 14-2
TROUBLESHOOTING STRATEGY . . . . . . 14-2
SYMPTOM CHART. . . . . . . . . . . . . . . . . . . 14-3
SYMPTOM PROCEDURES . . . . . . . . . . . . 14-3
ON-VEHICLE SERVICE . . . . . . . . . . .14-26
ENGINE COOLANT LEAK CHECK . . . . . . 14-26
RADIATOR CAP PRESSURE CHECK . . . . 14-27
ENGINE COOLANT REPLACEMENT . . . . 14-27
ENGINE COOLANT CONCENTRATION TEST14-29
FAN CONTROLLER CHECK . . . . . . . . . . . 14-29
FAN CONTROL RELAY CONTINUITY CHECK14-31
RADIATOR . . . . . . . . . . . . . . . . . . . . .14-32
REMOVAL AND INSTALLATION . . . . . . . . 14-32
THERMOSTAT . . . . . . . . . . . . . . . . . .14-35
REMOVAL AND INSTALLATION . . . . . . . . 14-35
INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . 14-38
WATER PUMP . . . . . . . . . . . . . . . . . .14-39
REMOVAL AND INSTALLATION . . . . . . . . 14-39
WATER HOSE AND WATER PIPE . .14-40
REMOVAL AND INSTALLATION . . . . . . . . 14-40
INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . 14-41
SPECIFICATIONS . . . . . . . . . . . . . . .14-42
FASTENER TIGHTENING
SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . 14-42
SERVICE SPECIFICATION . . . . . . . . . . . . 14-43
CAPACITIES . . . . . . . . . . . . . . . . . . . . . . . . 14-43
SEALANTS . . . . . . . . . . . . . . . . . . . . . . . . . 14-43

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-5
INSPECTION PROCEDURE 3: Radiator Fan and Condenser Fan do not Operate
.
CIRCUIT OPERATION
The fan controller is powered from fusible link
No.2.
The engine-ECU uses input signals from the A/C
switch, the water temperature sensor unit and the
vehicle speed sensor or the output shaft
speed sensor to control the speed of the
radiator fan motor and the condenser fan motor.
The engine-ECU controls the fan controller to
activate the radiator fan motor and the condenser
fan motor.
.
TECHNICAL DESCRIPTION
The cause could be a malfunction of the fan con-
troller power supply or earth circuit.
If the communication line wiring harness between
the fan controller and the engine-ECU is
short-circuited to earth, the radiator fan motor
and the condenser fan motor will not rotate.
The cause could also be a malfunction of input
signal from the A/C switch, the water temperature
sensor unit and the vehicle speed sensor
or the output shaft speed sensor to the
engine-ECU.
The cause could also be a malfunction of the fan
controller or the engine-ECU.

.
TROUBLESHOOTING HINTS
Malfunction of fusible link No.2
Malfunction of fan control relay
Malfunction of cooling fan motor and fan control-
ler
Malfunction of engine-ECU.
Damaged wiring harness or connector
Refer to component locations GROUP-1
Refer to configuration diagrams GROUP-1
Refer to circuit diagrams GROUP-1

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-7
STEP 3. Check the fusible link No.2.
Q: Is the fusible link No.2 in good condition?
YES : Go to Step 4.
NO : Replace the fusible link No.2. Then go to Step 24.
STEP 4. Measure the power supply voltage at fan control
relay connector A-10X.
(1) Disconnect fan control relay connector A-10X (remove the
fan control relay) and measure relay box side connector.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between fan control relay connector
A-10X terminal 4 and body earth.
The voltage should measure system voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Connect fan control relay connector A-10X (install the fan
control relay).
Q: Is the measured voltage system voltage?
YES : Go to Step 7.
NO : Go to Step 5.

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-8
STEP 5. Check the fan control relay connector A-10X.
Q: Is the connector in good condition?
YES : Go to Step 6.
NO : Repair the connector or replace the relay box. Then
go to Step 24.
STEP 6. Check the harness wire between fusible link No.2
and fan control relay connector A-10X terminal 4.
Q: Is the harness wire in good condition?
YES : An intermittent malfunction is suspected (Refer to
GROUP 00 - How to use troubleshooting 00-7).
NO : Repair the damaged harness wire. Then go to Step
24.
STEP 7. Check the fan control relay.
Refer to 14-31.
Q: Is the fan control relay in good condition?
YES : Go to Step 8.
NO : Replace the fan control relay. Then go to Step 24.

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-9
STEP 8. Check the fan control relay connector A-10X.
Q: Is the connector in good condition?
YES : Go to Step 9.
NO : Repair the connector or replace the relay box. Then
go to Step 24.
STEP 9. Check the harness wire between fan control relay
connector A-10X terminal 2 and fan controller connector
A-24 terminal 3.
Q: Is the harness wire in good condition?
YES : Go to Step 10.
NO : Repair the damaged harness wire. Then go to Step
24.

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-10
STEP 10. Measure the terminal voltage at fan control relay
connector A-10X.
(1) Disconnect fan control relay connector A-10X (remove the
fan control relay) and measure relay box side connector.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between fan control relay connector
A-10X terminal 3 and body earth.
The voltage should measure system voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Connect fan control relay connector A-10X (install the fan
control relay).
Q: Is the measured voltage system voltage?
YES : Go to Step 13.
NO : Go to Step 11.

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-11
STEP 11. Check the ECU connector B-21, intermediate
connector A-13 and fan control relay connector A-10X.
Q: Are there connectors in good condition?
YES : Go to Step 12.
NO : Repair or replace the connector. Then go to Step 24.

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-12
STEP 12. Check the harness wire between intermediate
connector A-13 terminal 2 and fan control relay connector
A-10X terminal 3.
Q: Are these harness wires in good condition?
YES : An intermittent malfunction is suspected (Refer to
00-7).
NO : Repair the damaged harness wire. Then go to Step
24.